1. Field of the Invention
The present application generally relates to suspension systems. More specifically, the present application relates to a suspension system for snow vehicles.
2. Description of the Related Art
A typical snow vehicle is designed to run on uneven snow surfaces and is thus provided with a suspension device for absorbing shocks caused by the unevenness of the snow surfaces.
Some suspension devices have front and rear arms that connect a slide rail to a body frame. A front shock absorber is interposed between the point where the front arm is connected to the body frame and the slide rail. A rear shock absorber has one end connected to the point where the rear arm is connected to the body frame. Another end of the rear shock absorber is connected to one end of a linkage member. Another end of the linkage member is connected to the point where the front arm is connected to the slide rail. One example of a suspension device is disclosed in Canada Patent No. 2,298,749.
The shock ratio (also referred to as lever ratio) represents the shock absorber stroke relative to the deflection of the slide rail. In known suspension devices, the shock ratio can only be set within a narrow range. For example, the rate of compression of the shock absorber stroke decreases as the deflection the slide rail increases causing the vehicle to bottom-out easily. Additionally, in known suspension devices, the shock ratio of the rear shock absorber, with respect to the slide rail deflection, can only be selected from a narrow range. Accordingly, it is difficult to attain a stroke range in which the suspension device both operates comfortably and can absorb energy at the same time.